Forgefix TechFast Roofing Sheets to Steel Hex Screws are used for joining metal roofing panels to steel frame buildings. The screws are fire resistant and corrosion resistant. Protected by Elementech corrosion resistant coating, salt spray tested to 1000 hours. Complies with EU Safety, Health and Environmental requirements. They are supplied with 16mm EPDM rubber washers. These Forgefix TechFast Roofing Sheets to Steel Hex Screws have the following specification: Size: 5.5 x 100mmEffective Thread Length: 77mmPack Size: 100Drill Tip: No.5 No.5 drill tip for self-drilling in heavy gauge steel up to 12.5mm. Forgefix Techfast Roofing Sheet To Steel Hex Screw & Washer No.5 Tip 5.5 X 100Mm Box 100 in Silver